The object of a heat exchanger assembly is to maximize heat transfer efficiency at the lowest possible manufacturing cost. Such heat exchangers include adjacent hollow tubes interconnected by fins. Typically, the tubes and fins are bonded together by a brazing process in an oven. This method is disclosed in U.S. Pat. Nos. 4,949,543, 5,042,574, 5,102,032, and 5,277,358, all to Cottone et al. To address the problem of bonding the fins to the tubes, U.S. Pat. No. 3,333,317 to Shockley discloses a method for making a heat exchanger by making individual hollow tubes with integral fins. In yet another disclosure, U.S. Pat. No. 5,490,559 to Dinulescu, a fin module is extruded having a flat wall for bonding with the flat wall of a hollow tube.
The prior art teaches the extrusion of a hollow tube having fins on one hand and the extrusion of a fin module on the other hand. Although the prior art methods and assemblies function satisfactorily, there remains a need to reduce the cost of manufacturing while meeting heat transfer requirements.